Method of producing modified phenol aldehyde resin



I Patented May 1, 1945 METHOD OF PRODUCING MODIFIED PHENOL ALDEHYDERESIN Samuel S. Gutkin, Brooklyn, N. Y., assignor to Falk & Company,Carnegie, Pa.,- a corporation of Pennsylvania No Drawing. ApplicationAugust 14, 1943,

Serial No. 498,729

8 Claims.

This invention relates to a specialized resinous phenol-aldehyde alkydproduct and relates more particularly to phenol-aldehyde alkyd productsthe specific properties of which are deter-' mined by a specializedmodification in the series of stages by which the resinous product ismade. The application herein is a continuation-in-part of my applicationSerial No. 306,291, filed No vember 27, 1939, now Patent No. 2,329,045,and of my application Serial No. 435,752, filed March 21, 1942.

Primarily the object of my invention is so to link the alkyd reactionsto a phenol-aldehyde condensate of the infusible, "Resite" or Bakelitetype that" there is obtained a resin possessing certain inherentproperties of phenol-aldehyde resins of that sort, such as the capacityto acquire density and gloss in a film, coupled in measure with thealkyd properties of flexibility, durability and susceptibility tomodification, by so conducting the process by which the resin isproduced that fusibility or solubility is retained in the reaction mass,or batch, during the formation of the resin without impairing in theproduct those characteristics of a full heat-hardening resin which havebeen above noted.

The further and more specific object'of my invention and the feature inwhich the resin which is the subject matter hereof differs from theresin specifically claimed in my above noted application Serial No.306,291 is to utilize as a modifying component included in the resin oneof the lower acyclic monocarboxylic acids or a mixture of such acids. Bythe term lower acyclic mono carboxylic acids as herein used, I intend todistinguish from the fatty oil acids, all of which are straight chainacids having more than 10 carbon atoms in their carbon chains. The fattyoil acids from which I herein distinguish are acyclic acids, such aslinseed oil acid, stearic acid,-eleostearic (tung oil) acid, oleic acid,palmitic acid, myristic acid, and lauric acid. The acyclicmonocarboxylic acids, the use of which is herein disclosed, distinguishfrom the fatty oil acids by having no more than 10 carbon atoms in theirerties of film-formation, adhesion, and strength. All are homogeneousproducts in that the exhibit no inherent tendency toward separationafter their formation. v

Generally stated my invention includes the initial formation of aphenol-aldehyde condensation product which-would be, if unmodified, ofthe Resite or Bakelite, or full heat-hardening and infusible sort, andincludes the involvement of that initial condensate in reactions andmodifications conducted with such determining and modifying reagents,and under such conditionsthat the fusibility and solubility of thereaction batch is maintained throughout the process and in measure isretained in the final product while also retaining in the productfundamental charnon-nuclear group; that is in the group attached to thecarboxyl of the acid.

The resinous products made in accordance with my invention differ fromthose disclosed in my above identified application Serial No. 306,291 bybeing as a class somewhat soften and more soluble than those otherproducts, and by having greater adhesiveness. They differ slightly fromeach other, but have in common the prop- 'densate. g

fundamentally infusible phenol-aldehyde con- I acteristics of theinfusible phenol-aldehyde con- T s I do by efiectively reacting thedensate with an unmodified polyhydric alcohol and then with a polybasiccarboxylic acid without destroying the above noted desirable propertiesinherent in the infusible phenol-aldehyde resins.

Following this I modify the resultant resinous product of condensationand partial esterification with an acyclic mono-carboxylic acid whichhas no more than 10 carbon atoms in its nonnuclear group.

As typical examples of aldehydes which may be reacted with phenol togive the phenol-aldehyde condensate, I may name acetaldehyde,butyraldehyde, propylaldehyde, crotonaldehyde, and formaldehyde. Astypical examples of unmodified polyhydric alcohols usable in my process,I may give glycerine, pentaerythritol, triethylene glycol, diethyleneglycol, and sorbitol. As typical of polybasic carboxylic acids which maybe used,

I may give phthalic anhydride, maleic anhydride,

malic acid, and fumaric acid. It may be stated generally that I may usein my process any aldehyde, any unmodified polyhydric alcohol, and anypolybasic carboxylic acid of the sort found suitable in the alkyd resinart.

As typical of acyclic monocarboxylic acids of the sort having no morethan 10 carbon atoms in their non-nuclear group, I may give acetic acid,propionic acid, butyric acid, valeric acid,.

caproic acid, acrylic acid, glycolic acid, ,crotonic acid, sorbic acid,lactic acid, hydracrylic acid,

hydroxy butyric acid, hydroxy valeric acid, glycine, alanine,aminobutyric acid, valine, leucine, isoleucine, norleucine, and the likeacyclic monocarboxylic acids.

tice. densate Imixed with it 154 grams of high-test Example No. 1

I mixed 300 grams of commercial (approximately 40%) formaldehyde and 221grams of commercial (approximately 100%) meta-paracresol with at least3.5 cc. sodium hydroxide catalyst in a concentration of 250 milligramsper cc.

This mixture was refluxed until the first si n of separation of wateroccurred. Such separation is indicated by clouding in a cooled sample,or region, of the reaction mass; and may be observed for instance in thecooled region of a glass reaction flask forming part of experimental orchecking apparatus. Upon the appearance of such cloud, and cooling thebatch, an opaque mass of resinous condensate formed, together with anappreciable quantity of free water.

It is to be understood that both the meta-paracresol and theformaldehyde of this example are common commercial materials, theformaldehyde being approximately 40% by volume and the meta-para-cresolbeing of usual commercial i purity.

Taking 50 grams of the condensate thus formed I washed it several timeswith water and removed as much water as possible by decantation andsqueezing, in accordance with my preferred prac- Prior to any additionalheating of the conglycerine forming a homogeneous mass. I then added 148grams of phthalic anhydride and heated the mixture until the water ofreaction came off as vapor and the phthalic anhydride was fused. It isdesirable that the temperature should not be raised substantially above320 F. until a further addition is made by adding the i selectedmonocarboxylic acid to the reaction mass,

or batch.

I have found that I may first heat to drive off water from thehomogeneous mass formed from the condensate and the glycerine and thenadd the polybasic carboxylic acid, or may add both the glycerine and thepolybasic carboxylic acid before heating and then heat. The point isthat in either case opportunity is given theglycerine as representativeof the unmodified polyhydric alcohols so to interact with the condensateas to form a homogeneous fusible mass therewith before reaction with thepolybasic carboxylic acid takes place, so that the product of reactionwith the polybasic carboxylic acid remains clear and homogeneous.

The resultant product,if subjected-to continued heating, to atemperature higher than 320 is a clear resinous material of plastictype, but less brittle than the simple phenol-formaldehyde It is,however.

condensate which forms its base. after reaction with the phthalicanhydride still susceptible to modification into products of fusible andsoluble sort. It will be noted that to retain the fusibility of thisintermediate product the condensate content of which is fundamentally ofthe infusible type I utilize an unmodified polyhydric alcohol which iseffective to keep the condensate in soluble condition for reaction withthe polybasic carboxylic acid.

400' F. With acetic acid, as with the other monocarboxylic acids of theclass herein disclosed, a temperature of about 400 F. was adequatetoincorporate the monocarboxylic acid in the reaction batch withoutclouding. The batch may, if desired, be brought to a temperaturesubstan-, tially above 400 E, if care be taken to cease heating when thfirst signs of gelation appear in the batch. v

The product was a thick, rigid, resinous material of water clear andpale straw color. It is indicated for use in adhesives, as a plasticizerfor nitro-cellulose, and when extended with suitable solvent, such asthe aromatic hydrocarbon solvents, ester solvents, alcohols or mixtures'of such solvents, is useful as a varnish coating.

As a variation under this same example, it may be noted that I haveadded as much as 100 grams of acetic acid, making the addition by smallincrements to avoid separation. It may be noted that in this example,and asa fact running through all the exemplifications of my'method, thatthe greater-the proportional addition of the monocarboxylic acid theless viscous will the product be, and the greater will be its solubilityin th common organic solvents.

Example No. 2 The procedure of this example was identical with that ofExample No. 1 and the materials Example N0. 3

The procedure of this example was identical with that of Example No. 1and'the materials used were identical with those of that example, exceptthat 116 grams of fumaric acid were used instead of 148 grams ofphthalic anhydride used in Example No. 1. f

It should be noted that examples paralleling Examples Nos. 2 and 3 arenot hereinafter given in conjunction with the use of other variablecompounds within the bounds of my invention as herein broadly disclosed.It is, however, to be understood that in every subsequent example inwhich the use of phthalic anhydride is indicated, an approximatelyequivalent molar content of maleic anhydride, fumaric acid, or otherpolybasic carboxylic acid, may be used equivalently to the phthalicanhydride as the polybasic carboxylic acid component of my resin, theprocedure in each instance being identical with that described whenphthalic anhydride-is used. I have observed only slight differencesbetween the products in which phthalic anhydride was used as thepolybasic carboxylic acid and those products in which some otherpolybasic carboxylic acid was used. Example No. 4

In this example the procedure and materials of Example No. l wereduplicated down to the final stage, in which stage lactic acid was addedas the monocarboxylic acid in place of the glacial acetic acid used inExample No. 1.

That is, to 50 grams of the resinous condensate made as in Example No.1, I added 154 grams of high-test glycerine, which formed a homogeneousmass with the condensate. Similarly. to the procedure of Example No. 1,148 grams of phthalic anhydride was added and the mixture was heated toabout 300 F. until capable of forming a clear bead.

Then 54 grams of lactic acid (85% U. S. P. was added, and heating wascontinued until the temperature reached about 400 F. and held at thistemperature for a short time. The temperature was then taken to about450 F. and the batch was cooled.

The product was a thick, viscous, rubbery,

resinous material of pale straw color. The material was turbid inappearance. The same uses are indicated for this product as for theproduct obtained by modification with glacial acetic acid.

Example No.

In this example the procedure and materials of Example No. 1 wereduplicated down to the final stage, in which stage acrylic acid wasadded as the monocarboxylic acid in place of the glacial acetic acidusedin Example No. l. '76 grams of acrylic acid were added in smallincrements to a partial esterification product made as in Example No. 1,while raising the temperature of the reaction mass, or batch, from themaximum temperature of the next preceding stage, or about 300 F., to atemperature of about 400 F. The batch was held at that temperature for ashort time, and the temperature was then raised to about 450 F. Thebatch was then cooled.

Apparently all of the acrylic acid went into the batch to give aresinous product of the same light color obtained by addition of glacialacetic acid in the final modification. When spread in a film as fordeposit from solution.in a suitable organic solvent such as the aromatichydro carbon solvents, the film exhibited hardness.

slightly greater than that obtained in the example in which acetic acidwas used.

Example No. 6

the next preceding stage, or about 300 F., to a' temperature of about400 F. The batch was held at that temperature for a short time, andcooled.

The product was water clear and of straw I color. It-was. a tacky andviscous solid resinous material.

Example No., 7

I mixed 215 grams of commercial phenol (approximately 100%) ,with 165grams of commercial acetaldehyde (approximately 100%) together with 11cc. of sodium hydroxide catalyst in a concentration of .250 milligrams,per cc. This mixturewas refluxed until the. first sign of separation of.water occurred. Such separation is indicated by clouding in a cooledsample or region of the reaction massand may be observed. for instance,in the cool region of the glass reaction flask forming part of theexperimental or checking apparatus. .Upon the appearance of such cloudand cooling the batch, an opaque mass of resinous condensate is formedtogether with an appreciable quantity of free Water.

Taking 50 grams of the condensate thus formed, I mixed with it .154grams of high-test glycerine, forming a homogeneous mass. I then added148 grams of phthalic anhydride with heating'to a temperature of about300 F., to drive off the water of reaction as a vapor and to fuse thephthalic anhydride. During this procedure, I was careful that thetemperature was not raised substantially above 320 F. pending the nextstage of the process.

In effecting modification of the resinous material formed as above bypartial esterificationof the condensate in reaction with the phthalicanhydride, heating of the batch was continued and was held until thebatch was capable of forming a clear bead. At that stage and withoutpermitting the material to gel, I added 37 grams of glacial acetic acidwith heating of the batch from the maximum temperature of the stage nextpreceding, which is about 300 F.', to a temperature of about 400 F. Thebatch was held at that latter temperature for a short time,

and then cooled.

The product was a dark and clear viscous resinous material.

Paralleling the procedure as described in Ex amples Nos. 1, 2, and 3, Imake to the partial esterification products as produced in Example No. 7given above and in variants of that example in which phthalic anhydridewas replaced by maleic acid and fumaric acid, addition of the severalmonocarboxylic acids described in Examples Nos. 4, 5, and 6, inclusive,thus similarly making addition of lactic .acid, acrylic acid, andglycine.

The results were consistently similar to those,

arrived at in Example No. 7. v Example No. 8

I mixed 300 grams of formaldehyde (approximately 40%) and 215 grams ofphenol (approximately with 11' cc. of sodium hydroxide catalyst in aconcentration of 250 milligrams per cc. This mixture was refluxed untilthe first sign of separation of water occurred. Such separation isindicated-by clouding in a cooled sample, or region, of thereactionmass; and may be observed for instance in the cooled region of aglass reaction fiask forming part of experimental or checkingapparatus.

Upon the appearance of such cloud, and cooling the batch, an opaque massof resinous condensate formed, together with an appreciablequantity offree water.

Taking 50 grams of the condensate thus formed I, washed it several timeswith water and removed as much water aspossible by decantation andsqueezing, in accordance with my preferred practice. Prior to anyadditional heating of the condensate, I mixed with it 154 grams ofhightest. glycerine forming a homogeneous mass. I

then added 148 grams of phthalic anhydride and heated the mixture tosuchtemperature (about 300-F.) that the. water of reaction came off asvapor and the phthalic anhydride was fused, taking care that thetemperature was not, raised substantially above 820"- F. pending thenextstage of the process. I

In eliecting modification of the resinous material formed as above byefi'ective esterification of the condensate and reaction with thephthalic anhydride, heating'oi' the batch was continued and held to theformation of a clear head. -At

that stage and without permitting the materialto-gei, Iadded 37 grams ofglacial acetic acid with heating from the maximum temperature 'of thestage next preceding to the temperature of about 400 F.

The product wa in its properties closely similar to the productsSimilarly produced by successive reactions with a condensate formed frommeta-para-cresol and formaldehyde, and was lighter in color than theproduct made by reactions with a condensate formed from phenol andacetaldehyde. The process was conducted in exactly the same manner, andthe same principles' and considerations as in Example No. 1 obtained.

Paralleling the procedure as described in Examples Nos. 1, 2, and 3, Ihave made to the partial esterification products as produced in ExampleNo. '8 above given, and to variants of that example in which phthalicanhydride was replaced by maleic acid and fumaric acid, addition of theseveral monocarboxylic acids the use of which is described in ExamplesNos. 4, 5, and 6, thus similarly making an addition of lactic acid,acrylic acid, and glycine. The results were consistently similar tothose arrived at in Examples Nos. 4'to 8 inclusive.

Example No. 9

I mixed 221 grams of commercial (approximately 100%) meta-para-cresolwith 165 grams of commercial (approximately 100%) acetaldehyde with atleast 3.5 cc. sodium hydroxide catalyst in a concentration of 250milligrams per cc. This mixture was refluxed until the first sign ofseparation of water occurred. Such separation ,is indicated by'cloudingin a'cooled sample, or region, of the reaction mass; and may be observed for instance in the cooled region of a glass reaction flaskforming part of experimental or checking apparatus. Upon the appearanceof such cloud, and cooling the batch, an opaque mass of resinouscondensate formed, together with an appreciable quantity of free water.

Taking 50 grams of the, condensate thus formed, I mixed with it 154grams of high-test glycerine, forming a homogeneous mass. I then added148 grams of phthalic anhydride and heated the mixture to suchtemperature (about 300 F.) that the water of reaction came off as vaporand the phthalic anhydride was fused, taking care that the temperaturewas not raised substantially above 320 F. pending the next stage of theprocess.

In effecting modification of the resinous material formed as above byeffective esterification of'the condensate and reaction withphthalic'anhydride, heating of the batch was continued and held to theformation of a clear head. At that stage and without permitting thematerial to gel,

, I added 37 grams of glacial acetic acid with heat-' amples Nos. 1,- 2,and 3, I have made to the partial esterification products as produced inExample No. 9 above given, and in variants of that example in whichphthalic anhydride was replaced by maleic acid and fumaric acid,addition of the several monocarboxylic acids the use of which isdescribed in Examples Nos. 4, 5, and 6, thus similarly making additionof lactic acid, acrylic acid, and glycine. The results were consistentlysimilar to those arrived at in Examples Nos. 4, 5, and 6.

Example No. 10

To 100 parts by weight of the resinous product obtained in Example No.1, I added 100 parts by weight of linseed oil, the temperature of thebatch being maintained at about 430 F. while the linseed oil was veryslowly added. The product was a coating material of oleoresinous naturehaving by virtue of its resin content exceptional capacity to acquiregloss and hardness in a film.

Example No. 11

To 100 parts by weight of the resinous product made in accordance withExample No. 4, I added 100 parts by weight of linseed oil, thetemperature of the resinous productbieng maintained at about 430 F.while the linseed oil was very slowly added. The product was a coatingmaterial having by virtue of its resin content exceptional-capacity toacquire gloss and hard-'.

ness in a film.

Example N0. 12

To 100 parts by weight of the resinous product obtained from theprocedure of Example No.

9, I added 100 parts by weight of linseed oil, the

temperature oi the resinous product-being maintained at about 430 F.while the linseed oil was very slowly added. The product was a coatinmaterial having by virtue of its resinous content exceptional capacityto acquire gloss and hardness in a film.

The procedure of Example Nos. 10, 11, and 12 was duplicated, adding,however, 100 parts by weight of soya bean oil in place of the linseedoil added in those examples.

It has been noted that the temperature at which condensation takes placeis relatively low, being for example of an order exemplified by refluxconditions such as are typical in making phenol-aldehyde condensates of,the infusible "Resite or Bakelite type, in distinction from the fusible,or Novolak, type condensates. To insure the formation of a condensate ofthe desired Resite type, I use in the initial condensate a phenolselected from the group of phenols consisting of meta-para-cresol,phenol, and

- xylenol, and do not use the phenolics, such as butyl-phenol, orpara-tertiary amyl-phenol, which tend.t0 give a phenol-aldehydecondensate which is inherently more fusible and which is incapable ofimparting to the final products the properties of hardness and glosstypical of the infusible, Resite, type phenol-aldehyde condensates. 4

Although I use an initial condensate inherently possessing fullheat-hardening properties, by using an unmodified polyhydric alcohol, bycausing that alcohol to s'olubilize the initial condensate,

. and without the use of added solubilizing agents,

I am ableto maintain the reaction mass, or batch, in a fusible conditionwhichpermits the reaction with the polybasic carboxylic acidappropriately to take place. Also by the avoidance of high temperaturein the batch prior to the addition of the acyclic monocarboxylic acid inthe final stage, the batch being still in soiubilized condition byvirtue of the use of unmodified polyhydric alcohol and the conditions ofits use, I am enabled to make substantial additions of monocarboxylicacids of the sort to which this present invention relates. The quantityofsuch monocarboxylic acids which are added is not critical, but asabove noted increased quantity tends to increased solubility of theresinous products obtained.

. all of which I have found suitable.

Since in distinction from my previous application to which reference hasbeen above made, I utilize as the final modifying ingredient of my resinmonocarboxylic acid which conforms to specified requirements in being anacyclic monocarboxylic acid having no more than '10 carbon atoms in itsnon-nuclear group attached to the carboxyl of the acid, I have hereinnoted and exemplified a relatively great number of such monocarboxylicacids. The employment of various polybasic carboxylic acids in makingalkyd modification in phenol-aldehyde resins having been fully developedin the art, I have exemplified herein phthalic anhydride, maleicanhydride,

' malic acid, and fumaric acid. It is to be understood, however, thatany other polybasic carboxylic acid which the art has found to besuitable for the alkyd'modification of phenol-aldehyde resins may beemployed while conforming to the principles of my invention, andfollowing the procedure of my method as outlined in the examples givenabove. -I may also give as exemplary of polyhydric alcohols other thangiycerine, pentaerythritol, triethylene glycol, diethylene glycol, andsorbitol. When used as equivalents for glycerine these alcohols are usedin quantities of molar equivalency with the glycerine specifically notedin the examples given above.

As exemplary of aldehydes which may beused, I may name formaldehyde,butyraldehyde, pro: pylaldehyde, acetaldehyde, and crotonaldehyde,

Other unmodified polyhydric alcohols, and aldehydes, which the art hasfound suitable for use in the modification or formation ofphenol-aldehyde condensates may be used in appropriate molarproportions.

It may be emphasized that the result of my.

method is to give resins suitable for various uses, and particularlyadapted for molding, for use in electrical insulating varnishes, coatingcompositions, and adhesives, in which'the initial condensate is a resinof full heat-hardening properties, and in which the advantageousfeatures attendant upon those properties are retained, by so includingthe polyhydric alcohol and the polybasic carboxylic acid in the batch bywhich the resin is formed that I amable to obtain the desired sequenceof reactions without the addition of any solubilizing agent, such as aresin, or by the addition of a solubilizing acid, such as amonocarboxylic acid prior to reaction with polybasic carboxylic acid.The product resins thus retain hardness, gloss, and alkali resistancecharacteristic of molding resins of the full heat-hardening type, inresins suitable for use in adhesives and coatings. In these resins,also, the character of the monocarboxylic acid included as a modifyingaddition in the process of their manufacture gives the resins effectivesolubility in a wide range of commercial solvents.

I claim as my invention:

1. Theherein described method of producing a modified phenol-aldehyderesin by the sequentialsteps of forming an initial phenol-aldehydecondensate of the infusible type by refluxing aldehyde with a phenolselected from the group consisting of meta-para-cresol, phenol, andxylenol in the presence of an alkaline catalyst in the reactingproportion of at least 1.5 mols. of aldehyde to 1 mol. of the phenol tothe stage at which water separates on cooling, forming a homogene ousmass of the condensate and an unmodified polyhydric alcohol and reactingthe said mess with a polybasic carboxylic acid with heating to atemperature adequate to drive off water and to fuse the polybasiccarboxylic acid and not substantially exceeding 320 F. in the absence ofa solubilizing agent and holding to a clear bead, in the reaction massthe polyhydric acid being in excess of the polybasic carboxylic acid andboth being in excess of the initial condensate, and with heating to atemperature of about 400" F., making to the partial esterificationproduct thus formed at least one addition of a monocarboxylic acidselected from the class consisting of the acyclic monocarboxylic acidshaving no more than 10 carbon atoms in the group attached to the car--UXY-l of the acid and mixtures of such acids.

2. The herein described method of producing a modifiedphenol-formaldehyde resin by the sequential steps of forming an initialphenol-formaldehyde condensate of the infusibl'e type by refiuxingformaldehyde with a phenol selected from the group consisting ofmeta-para-cresol, phenol, and xylenol in the presence of an alkalinecatalyst in the reacting proportion of at least 1.5 mols. offormaldehyde to 1 mol. of the phenol to a stage at which water separateson cooling, forming a homogeneous mass of the condensate and anunmodified polyhydric alcohol and reacting the said mass with apolybasic carboxylic acid with heating to a temperature adequate todrive off water 4 in the reaction mass the polyhydric alcohol being inexcess of the polybasic carboxylic acid and both being in excess of theinitial condensate, and with further heating to a temperature of about400 F.

making to the partial esterification product thus formed at least oneaddition of a monocarboxylic acid selected from the class consisting ofthe acyclic monocarboxylic acids having no more than 10 carbon atoms inthe group attached to the carboxyl of the acid and mixtures of suchacids.

3. The herein described method of producing a modified phenol-aldehyderesin by the sequential steps of forming an initial phenol-aldehydecondensate of the infusible type by refluxing aldehyde with a phenolselected from the group consisting of meta-para-cresol, phenol, andxylenol in the presence of an alkaline catalyst in the reactingproportion of at least 1.5 mols. of aldehyde to 1 mol. of the phenol tothe stage at which water separates on cooling, forming a homogeneousmass of the condensate and an unmoditied polyhydric'alcohol and reactingthe said mass with a polybasic carboxylic acid with heating to atemperature adequate to drive off water and to fuse the polybasiccarboxylic acid and not sub stantially exceeding 320 F. in the absenceof asolubilizing agent and holding to a clear bead, in the reaction massthe polyhydric alcohol being in excess of the polybasic carboxylic acidand both being in excess of the initial condensate, and with heating toa temperature of about 400 F. making to the partial esterificationproduct thus formed at least one addition of glacial acetic acid.

4. The hereindescribed method of producing a modifiedphenol-formaldehyde resin by the sequential steps of forming an initialphenolformaldehyde condensate of the infusible type by refluxingformaldehyde with a phenol selected from the group consisting ofmeta-para-cresol, phenol, and xylenol in the presence of an alkalinecatalyst in the reacting proportion of atleast 1.5 mols. of formaldehydeto 1 mol. of the phenol to a stage at which water separates on cooling,forming a. homogeneous mass of the condensate and an unmodified'polyhydric alcohol and reacting the said mass with apolybasiccarboxylicacid with heating to a temperature adequate to driveoff water and to fuse the polybasic carboxylic acid and notsubstantially exceeding 320 F. in the absence of a solubilizing agentand holding to a clear bead; in the reaction mass the polyhydric alcoholbeing in excess of the poly-- basic carboxylic acid and both being inexcess of the initial condensate, and with further heating to atemperature of about 400 F. making to the partial esterification productthus formed at least one addition of glacial acetic acid.

5. The herein described method of producing a modified phenol-aldehyderesin' by the sequential steps of forming an initial phenol-aldehydecondensate of the in-fusible type by refluxing aldehyde with a phenolselected from the group consisting of meta-para-cresol, phenol, andxylenol in the presence of an alkaline catalyst in the reactingproportion of at least 1.5 mols. of aldehyde to 1 mol. of the phenol tothe stage at which water separates on cool n forming a homogeneous massof the condensate and an unmodified polyhydric alcohol and reacting thesaid mass with a polybasic carboxylic acid with heating to a temperatureadequate to drive ofi water and to fuse the polyjbasic carboxylicacidand not substantially exceeding 320 F. in the absence of a solubilizingagent and holding to a clear bead, in the reaction mass the polyhydricacid being in excess of the polybasic carboxylic acid and both being inexcess of the initial condensate, and with heating to a temperature ofabout 400 F. making to the partial esterification product thus formed atleast one addition of lactic acid.

6. The herein described method of producing amodifiedphenol-formaldehyde resin by the sequential steps .of forming an initialphenolformaldehyde condensate of the infusible type by refluxingformaldehyde with a phenol selected from the group consisting ofmeta-para-cresol, phenol, and xylenol in the presence of an alkalinecatalyst in the reacting proportion of at least 1.5

F. in the absence of a solubilizing agent and holding to a clear bead,in the reaction mass the polyhydric alcohol being in excess of thepolybasic carboxylic acid and both being in excess of the initialcondensate, and withfurther heating to a temperature ofabout 400 F.making to the partial esterification product thus formed at least oneaddition of lactic acid.

'7. The herein described method of producing a modified phenol-aldehyderesin by 'the sequential steps of forming an initial phenol-aldehydecondensate of the infusible. type by refluxing aldehyde with a phenolselected from the group consisting of meta-para-cresol, phenol, and xylI enol in the presence of an alkaline catalyst in the reactingproportion of at least 1.5 mols. of

aldehyde to 1 mol. of the phenol to the stage at which waterv separateson cooling, forming a homogeneous mass of the condensate and anunmodified polyhydric alcohol and reacting the said mass with apolybasic carboxylic acid with heating to a temperature adequate todrive off water and to fuse the polybasic canboxylic acid and notsubstantially exceeding 320 F. in the absence of a solubilizing agentand holding to a clear bead,

. alkaline catalyst in the reacting proportion of mols. of formaldehydeto 1 mol. of the phenol to a stage at which water separates on cooling,forming a homogeneous mass of the,con densate and an unmodifiedpolyhydric alcohol and reacting the said mass with a polybasiccarboxylic acid with heating to a, temperature adequate to drive allwater and to fuse the polybasic carboxylic acid and not substantiallyexceeding 320 at least 1.5 mols. of formaldehyde to 1 mol. of the phenolto a stage at which water separates on cooling, forming a, homogeneousmass of the condensate and an unmodified polyhydric alcohol and reactingthe said mass with a polybasic carboxylic acid with heating to atemperature adequate 'to drive off water and to fuse the polybasiccarboxylic acid and not substantially exceeding 320 F. in the absence ofa solubilizing agent and holding to a clear bead, in thereaction massthe polyhydric alcohol being in excess of the poly- -basic carboxylicacid and both being in excess of the initial condensate, and withfurther heating to a temperature of about 400 F. making to the partialesterification product thus formed at least one addition of acrylicacid.

' SAMUEL S. GUTIGN.

